I cannot open iPhoto after upgrading latest apple updates. Getting a message latest iPhoto version is not available in the US

scroll down through these forum pages to find the answer, many questions of this nature posted.

Go to the App Store and check out the Purchases List. If iPhoto is there then it will be v9.6.1

If it is there, then drag your existing iPhoto app (not the library, just the app) to the trash

Install the App from the App Store.

Sometimes iPhoto is not visible on the Purchases List. it may be hidden. See this article for details on how to unhide it.

http://support.apple.com/kb/HT4928

One question often asked: Will I lose my Photos if I reinstall?

iPhoto the application and the iPhoto Library are two different parts of the iPhoto programme. So, reinstalling the app should not affect the Library. BUT you should always have a back up before doing this kind of work. Always.